标签: versus

FuzzyLogicVersusPISpeedControlinHigh-PerformanceACDrives-AComparison

OnceyoudecidethataDigitalSignalProcessorisrightforyourapplication,youneedawaytogetstarted.Manymanufacturerswillsellyoualowcostevaluationkit,allowingyoutoexperiencetheirproductsfirst-hand.Theseareagreateducationaltool;itdoesn'tmatterifyouareanoviceorapro,theyarethebestwaytobecomefamiliarwithaparticularDSP.Forinstance,AnalogDevicesprovidestheEZ-KIT®LitetoteachpotentialcustomersaboutitsSHARC®familyofDigitalSignalProcessors.Foronly$179,youreceiveallthehardwareandsoftwareyouneedtoseetheDSPinaction.Thisincludes"canned"programsprovidedwiththekit,aswellasapplicationsyoucanwriteyourselfinassemblyorC.SupposeyoubuyoneofthesekitsfromAnalogDevicesandplaywithitforafewdays.Thischapterisanoverviewofwhatyoucanexpecttofindandlearn.TheADSP-2106xfamilyInCHAPTERGettingStartedwithDSPs29OnceyoudecidethataDigitalSignalProcessorisrightforyourapplication,youneedawaytogetstarted.Manymanufacturerswillsellyoualowcostevaluationkit,allowingyoutoexperiencetheirproductsfirst-hand.Theseareagreateducationaltool;itdoesn'tmatterifyouareanoviceorapro,theyarethebestwaytobecomefamiliarwithaparticularDSP.Forinstance,AnalogDevicesprovidestheEZ-KITLitetoteachpotentialcustomersaboutitsSHARCfamilyofDigitalSignalProcessors.Foronly$179,youreceiveallthehardwareandsoftwareyouneedtoseetheDSPinaction.Thisincludes"canned"programsprovidedwiththekit,aswellasapplicationsyoucanwriteyourselfinassemblyorC.Suppos……

DigitalSignalProcessingiscarriedoutbymathematicaloperations.Incomparison,wordprocessingandsimilarprogramsmerelyrearrangestoreddata.ThismeansthatcomputersdesignedforbusinessandothergeneralapplicationsarenotoptimizedforalgorithmssuchasdigitalfilteringandFourieranalysis.DigitalSignalProcessorsaremicroprocessorsspecificallydesignedtohandleDigitalSignalProcessingtasks.Thesedeviceshaveseentremendousgrowthinthelastdecade,findinguseineverythingfromcellulartelephonestoadvancedscientificinstruments.Infact,hardwareengineersuse"DSP"tomeanDigitalSignalProcessor,justasalgorithmdevelopersuse"DSP"tomeanDigitalSignalProcessing.ThischapterlooksathowDSPsaredifferentfromothertypesofmicroprocessors,howtodecideifaDSPisrightforyourapplication,andhowtogetstartedinthisexcitingnewfield.Inthenextchapterwewilltakeamoredetailedlookatoneofthesesophisticatedproducts:theAnalogDevicesSHARC®family.CHAPTERDigitalSignalProcessors28DigitalSignalProcessingiscarriedoutbymathematicaloperations.Incomparison,wordprocessingandsimilarprogramsmerelyrearrangestoreddata.ThismeansthatcomputersdesignedforbusinessandothergeneralapplicationsarenotoptimizedforalgorithmssuchasdigitalfilteringandFourieranalysis.DigitalSignalProcessorsaremicroprocessorsspecificallydesignedtohandleDigitalSignalProcessingtasks.Thesedeviceshaveseentremendousgrowthinthelastdecade,findinguseineverythingfromcellulartelephonestoadvancedscientificinstruments.Infact,hardwareengineersuse"DSP"tomeanDigitalSignalProcessor,justasalgorithmdevelopersuse"DSP"tomeanDigitalSignalProcessing.Thischap……

AsimplemethodtocalculatepoweramplifierefficiencyversusoutputpowerproductforumAsimplemethodtocalculatepoweramplifierefficiencyversusoutputpowerLookingforanewmethodtosavevaluabledesigntime?ThisnewmethodallowsthedesignertoevaluateaPA’sefficiencywithoutactualbuildup.ByFrankDellaCortetransistors.Althoughnotnecessaryforthisdiscussion,aPAdesignerneedstoconsidertheoptimaloperatingpointforthePAtransistortoobtainmaximumefficiency.ForClass-ABmode,thePA’soutputpowercapabilityversusitsloadline(Rlcap)isgivenbythefollowingrelationship:Pcap=(Veff)2/2Rlcap,WhereVeff=Vcc-VsatOncetheloadlineisset,themaximumpowertransfer,hencemaximumPAefficiency,willoccurwhentheloadisequaltotheloadline.Thetypicalloadlinesfor3-voltPAsrunontheorderof2to5.Inpra……